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Record W4405997129 · doi:10.1080/23748834.2024.2439642

Cross-country policy comparison of 30 km/h speed limits

2025· article· en· W4405997129 on OpenAlexafffundabout
Lauren Pearson, Megan Oakey, Breanna Nelson, Mojgan Karbakhsh, Shazya Karmali, Ben Beck

Bibliographic record

VenueCities & Health · 2025
Typearticle
Languageen
FieldEngineering
TopicTraffic control and management
Canadian institutionsBC Centre for Disease ControlSpinal Cord Injury BC
FundersNational Health and Medical Research CouncilAustralian Research CouncilBritish Columbia Centre for Disease Control
KeywordsEnvironmental science

Abstract

fetched live from OpenAlex

30 km/h speed zones are one of the most cost-effective road safety interventions to enhance the safety and liveability of local streets. However, only two zones are currently implemented in the state of Victoria, Australia, and these zones are not widely adopted across Australia. Greater understanding of the barriers to implementation is needed to rapidly advance implementation of this effective road safety intervention. We aimed to identify and explore barriers and enablers of implementation of 30 km/h speed limits in the state of Victoria, Australia, and compare this to implementation in an area where 30 km/h speed zones have been implemented successfully – British Columbia, Canada. We conducted 26 semi-structured interviews with relevant policy partners. Data were analysed abductively through reflexive thematic analysis. Six key themes were identified: (i) Appetite for change; (ii) Policy misalignment; (iii) Lack of local evidence; (iv) Council capacity; (v) Need for ‘self-explaining’ roads, and (vi) Equity lessons in implementation. We demonstrated momentum and support for 30 km/h speed zones. However, state government policy reform is needed to enable easier implementation by local councils. This study provides critical insights into the complexity of implementing road safety interventions and opportunities to enhance systems to catalyse change.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.020
metaresearch head score (Gemma)0.038
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.092
Threshold uncertainty score0.183

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0200.038
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0010.001
Bibliometrics0.0020.003
Science and technology studies0.0020.001
Scholarly communication0.0020.002
Open science0.0010.003
Research integrity0.0010.002
Insufficient payload (model declined to judge)0.0040.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.017
GPT teacher head0.316
Teacher spread0.299 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations5
Published2025
Admission routes3
Has abstractyes

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